Free Tool

Radon Risk Calculator

See exactly how much reducing your home's radon level could lower your lifetime lung cancer risk — based on EPA risk tables for smokers and non-smokers.

Based on EPA data.This calculator uses lifetime risk estimates from the EPA's “A Citizen's Guide to Radon” (Table 1). Results represent population-level statistical risk, not personal medical prediction. Consult your healthcare provider and a certified radon professional for personalized guidance.

Your Inputs

5 pCi/L
0.4 (background)4.0 = EPA action level20 pCi/L
This level is at or above the EPA action level. Mitigation is strongly recommended.
1.0 pCi/L

Typical mitigation reduces radon by 50–99%. Most systems achieve 0.5–2.0 pCi/L post-mitigation.

30 yrs
1 year50 years

Risk Comparison

Lifetime lung cancer risk per 1,000 people exposed (30-year baseline)

At 5 pCi/L (current)9 in 1,000
At 1.0 pCi/L (after mitigation)2 in 1,000

Meaningful risk reduction

78%

reduction in lifetime lung cancer risk

How to Interpret This

A risk of 9 in 1,000 means that if 1,000 people lived at 5 pCi/L for their entire lives, approximately 9 of them would develop lung cancer from radon exposure.

The EPA's action level of 4.0 pCi/L corresponds to a lifetime risk of 7 per 1,000 non-smokers — higher than virtually any other environmental cancer risk regulated by the EPA.

Ready to take action?

First, know your home's actual radon level. A $15 test kit is all you need.

Data source:U.S. Environmental Protection Agency, “A Citizen's Guide to Radon” — Risk Table 1. Radon risk estimates assume continuous exposure over a lifetime (70 years) at indoor air concentrations. The EPA action level is 4.0 pCi/L (picocuries per liter).View EPA source →